Evidence for contributions of interactions of constituents to the anti-inflammatory activity of Hypericum perforatum

Hypericum perforatum L. attenuates depression by regulating Akkermansia muciniphila, tryptophan metabolism and NFκB-NLRP2-Caspase1-IL1β pathway

BACKGROUND

Gut microbiota dysbiosis significantly contributes to progression of depression. Hypericum perforatum L. (HPL) is traditionally used in Europe for treating depression. However, its mechanism remains largely underexplored.

PURPOSE

This study aims to investigate the pivotal gut microbiota species and microbial signaling metabolites associated with the antidepressant effects of HPL.

METHODS

Fecal microbiota transplantation was used to assess whether HPL mitigates depression through alterations in gut microbiota. Microbiota and metabolic profiling of control, chronic restraint stress (CRS)-induced depression, and HPL-treated CRS mice were examined using 16S rRNA gene sequencing and metabolomics analysis. The influence of gut microbiota on HPL's antidepressant effects was assessed by metabolite and bacterial intervention experiments.

RESULTS

HPL significantly alleviated depression symptoms in a manner dependent on gut microbiota and restored gut microbial composition by enriching Akkermansia muciniphila (AKK). Metabolomic analysis indicated that HPL regulated tryptophan metabolism, reducing kynurenine (KYN) levels derived from microbiota and increasing 5-hydroxytryptophan (5-HTP) levels. Notably, supplementation with KYN activated the NFκB-NLRP2-Caspase1-IL1β pathway and increased proinflammatory IL1β in the hippocampus of mice with depression. Interestingly, mono-colonization with AKK notably increased 5-hydroxytryptamine (5-HT) and decreased KYN levels, ameliorating depression symptoms through modulation of the NFκB-NLRP2-Caspase1-IL1β pathway.

CONCLUSIONS

The promising therapeutic role of HPL in treating depression is primarily attributed to its regulation of the NFκB-NLRP2-Caspase1-IL1β pathway, specifically by targeting AKK and tryptophan metabolites.

Hypericum perforatum: a comprehensive review on pharmacognosy, preclinical studies, putative molecular mechanism, and clinical studies in neurodegenerative diseases

The herb Hypericum perforatum, also referred to as St. John's wort, has drawn a lot of interest because of its potential therapeutic benefits in treating neurodegenerative illnesses. Due to the absence of effective therapies, illnesses like Alzheimer's and Parkinson's disease pose an increasing worldwide health concern. Because of its wide variety of phytochemicals, especially hyperforin, and hypericin, Hypericum perforatum is well known for its neuroprotective properties. These substances have proven to be able to affect different cellular processes linked to neurodegeneration. They can act as anti-inflammatory, antioxidant, and neurotransmitter system regulators, which may help halt neurodegenerative illnesses' progression. The use of Hypericum perforatum extracts and its contents has shown encouraging results in research on animal models of neurodegenerative disorders. These advantages include higher nerve cell survival, lowered oxidative stress, and higher cognitive performance. Underscoring its versatile potential to combat neurodegeneration, Hypericum perforatum has neuroprotective mechanisms that modulate neuroinflammation and prevent apoptotic pathways. In conclusion, Hypericum perforatum shows tremendous promise as a potential treatment for neurological illnesses due to its wide variety of phytochemicals. To completely comprehend its specific mechanisms of action and turn these discoveries into efficient clinical therapies, additional research is needed. Investigating Hypericum perforatum's function in neurodegenerative disorders may present new opportunities for the advancement of ground-breaking therapeutic strategies.

Hypericum perforatum L. and the Underlying Molecular Mechanisms for Its Choleretic, Cholagogue, and Regenerative Properties

Any defects in bile formation, secretion, or flow may give rise to cholestasis, liver fibrosis, cirrhosis, and hepatocellular carcinoma. As the pathogenesis of hepatic disorders is multifactorial, targeting parallel pathways potentially increases the outcome of therapy. Hypericum perforatum has been famed for its anti-depressive effects. However, according to traditional Persian medicine, it helps with jaundice and acts as a choleretic medication. Here, we will discuss the underlying molecular mechanisms of Hypericum for its use in hepatobiliary disorders. Differentially expressed genes retrieved from microarray data analysis upon treatment with safe doses of Hypericum extract and intersection with the genes involved in cholestasis are identified. Target genes are located mainly at the endomembrane system with integrin-binding ability. Activation of α5β1 integrins, as osmo-sensors in the liver, activates a non-receptor tyrosine kinase, c-SRC, which leads to the insertion of bile acid transporters into the canalicular membrane to trigger choleresis. Hypericum upregulates CDK6 that controls cell proliferation, compensating for the bile acid damage to hepatocytes. It induces ICAM1 to stimulate liver regeneration and regulates nischarin, a hepatoprotective receptor. The extract targets the expression of conserved oligomeric Golgi (COG) and facilitates the movement of bile acids toward the canalicular membrane via Golgi-derived vesicles. In addition, Hypericum induces SCP2, an intracellular cholesterol transporter, to maintain cholesterol homeostasis. We have also provided a comprehensive view of the target genes affected by Hypericum's main metabolites, such as hypericin, hyperforin, quercitrin, isoquercitrin, quercetin, kaempferol, rutin, and p-coumaric acid to enlighten a new scope in the management of chronic liver disorders. Altogether, standard trials using Hypericum as a neo-adjuvant or second-line therapy in ursodeoxycholic-acid-non-responder patients define the future trajectories of cholestasis treatment with this product.

Outstanding Antibacterial Activity of Hypericum rochelii-Comparison of the Antimicrobial Effects of Extracts and Fractions from Four Hypericum Species Growing in Bulgaria with a Focus on Prenylated Phloroglucinols

Microbial infections are by no means a health problem from a past era due to the increasing antimicrobial resistance of infectious strains. Medicine is in constant need of new drugs and, recently, plant products have had a deserved renaissance and garnered scientific recognition. The aim of this work was to assess the antimicrobial activity of ten active ingredients from four Hypericum species growing in Bulgaria, as well as to obtain preliminary data on the phytochemical composition of the most promising samples. Extracts and fractions from H. rochelii Griseb. ex Schenk, H. hirsutum L., H. barbatum Jacq. and H. rumeliacum Boiss. obtained with conventional or supercritical CO₂ extraction were tested on a panel of pathogenic microorganisms using broth microdilution, agar plates, dehydrogenase activity and biofilm assays. The panel of samples showed from weak to extraordinary antibacterial effects. Three of them (from H. rochelii and H. hirsutum) had minimum inhibitory concentrations as low as 0.625-78 mg/L and minimum bactericidal concentrations of 19.5-625 mg/L against Staphylococcus aureus and other Gram-positive bacteria. These values placed these samples among the best antibacterial extracts from the Hypericum genus. Some of the agents also demonstrated very high antibiofilm activity against methicillin-resistant S. aureus. Ultra-high-performance liquid chromatography-high-resolution mass spectrometry revealed the three most potent samples as rich sources of biologically active phloroglucinols. They were shown to be good drug or nutraceutical candidates, presumably without some of the side effects of conventional antibiotics.

PVA-Based Electrospun Biomembranes with Hydrolyzed Collagen and Ethanolic Extract of Hypericum perforatum for Potential Use as Wound Dressing: Fabrication and Characterization

Biological, physicochemical, structural, and thermal properties of PVA-based electrospun wound dressings added with hydrolyzed collagen (HC) and different concentrations of Hypericum perforatum ethanolic extract (EEHP) were studied. Membrane characterization was carried out by X-ray diffraction, Fourier infrared spectroscopy, differential scanning calorimetry, barrier properties, scanning electron microscopy, image analysis (diameter and pore size), as well as antimicrobial and anti-inflammatory activities. Results showed that the PVA/HC/EEHP materials, fabricated under controlled conditions of temperature and humidity, generated fiber membranes with diameters between 140−390 nm, adequate porosity and pore size for cell growth (67−90% and 4−16 µm, respectively), and good barrier properties (0.005−0.032 g·m−2 s−1) to be used in the treatment of conditions on the skin, and was even better than some commercial products. Finally, they showed to have anti-inflammatory (>80%), and antimicrobial activity against S. aureus and S. epiderm. Furthermore, higher crystalline structure was observed according to the EEHP concentration. In addition, this is the first report in which PVA/HC/EEHP membranes are successfully fabricated and characterized.

Ca' Granda, Hortus simplicium: Restoring an Ancient Medicinal Garden of XV-XIX Century in Milan (Italy)

This work is based on the study of 150 majolica vases dated back to the mid XVII century that once preserved medicinal remedies prepared in the ancient Pharmacy annexed to the Ospedale Maggiore Ca' Granda in Milan (Lombardy, Italy). The Hortus simplicium was created in 1641 as a source of plant-based ingredients for those remedies. The main objective of the present work is to lay the knowledge base for the restoration of the ancient Garden for educational and informative purposes. Therefore, the following complementary phases were carried out: (i) the analysis of the inscriptions on the jars, along with the survey on historical medical texts, allowing for the positive identification of the plant ingredients of the remedies and their ancient use as medicines; (ii) the bibliographic research in modern pharmacological literature in order to validate or refute the historical uses; (iii) the realization of the checklist of plants potentially present in cultivation at the ancient Garden, concurrently with the comparison with the results of a previous in situ archaeobotanical study concerning pollen grains. For the species selection, considerations were made also regarding drug amounts in the remedies and pedoclimatic conditions of the study area. Out of the 150 vases, 108 contained plant-based remedies, corresponding to 148 taxa. The remedies mainly treated gastrointestinal and respiratory disorders. At least one of the medicinal uses was validated in scientific literature for 112 out of the 148 examined species. Finally, a checklist of 40 taxa, presumably hosted in the Hortus simplicium, was assembled.

Investigation of Active Anti-Inflammatory Constituents of Essential Oil from Pinus koraiensis (Sieb. et Zucc.) Wood in LPS-Stimulated RBL-2H3 Cells

In a previous study, we demonstrated the anti-inflammatory activity of the essential oil extracted from Korean pine (Pinus koraiensis, Sieb. et Zucc.) wood. This study aims to investigate the active anti-inflammatory constituents of P. koraiensis oil. The essential oil was extracted from P. koraiensis wood by hydrodistillation and was divided into six fractions (A-F) through fractional distillation. Then, the anti-inflammatory activities of the fractions (A-F) were determined. Fractions A and F markedly downregulated the production of pro-inflammatory cytokines as well as the secretion of β-hexosaminidase in lipopolysaccharide (LPS)-stimulated RBL-2H3 cells. The main constituents of the active anti-inflammatory A and F fractions were (+)-α-pinene, (-)-β-pinene, (+)-α-terpineol, 3-carene, (+)-limonene, and longifolene. These six single compounds decreased the expression of inflammatory-related genes (i.e., IL-4 and IL-13) as well as the secretion of β-hexosaminidase in LPS-stimulated RBL-2H3 cells. (+)-α-Pinene, (-)-β-pinene, (+)-α-terpineol, and longifolene exhibited the strongest effects; these effects were comparable to those of the positive control (i.e., dexamethasone). The findings indicate that the interactions between these components exhibit potential for the management and/or treatment of inflammatory conditions as well as base structures for the development of novel anti-inflammatory drugs.

Whole-genome sequence data of Hypericum perforatum and functional characterization of melatonin biosynthesis by N-acetylserotonin O-methyltransferase

Hypericum perforatum is among the most commonly used herbal remedies and supplements. The aerial plant parts are often used to treat depression. Due to the lack of genomic information of H. perforatum, the gene networks regulating secondary metabolite synthesis remain unclear. Here, we present a high-quality genome for H. perforatum with a 2.3-Mb scaffold N50. The draft assembly covers 91.9% of the predicted genome and represents the fourth sequenced genus in the order Malpighiales. Comparing this sequence with model or related species revealed that Populus trichocarpa and Hevea brasiliensis could be grouped into one branch, while H. perforatum and Linum usitatissimum are grouped in another branch. Combined with transcriptome data, 40 key genes related to melatonin, hyperforin, and hypericin synthesis were screened and analyzed. Five N-acetylserotonin O-methyltransferases (HpASMT1-HpASMT5) were cloned and functionally characterized. Purified HpASMT3 protein converted N-acetylserotonin into melatonin with a V_max of about 1.35 pkat/mg protein. HpASMT1 and HpASMT3 overexpression in Arabidopsis mutants caused 1.5-2-fold higher melatonin content than in mutant and wild-type plants. The endogenous reactive oxygen species (ROS) in transgenic plants was significantly lower than ROS in mutant and wild-type plants, suggesting higher drought tolerance. The obtained genomic data offer new resources for further study on the evolution of Hypericaceae family, but also provide a basis for further study of melatonin biosynthetic pathways in other plants.

Medicinal plants as therapeutic options for topical treatment in canine dermatology? A systematic review

Background

Medicinal plants have been used traditionally since centuries for wound care and treatment of skin diseases both in human and animals. Skin diseases are one of the most common reasons for owners to take their dog to the veterinarian. The demands for treatment and prophylaxis of these diseases are broad. A wide range of bacteria including antibiotic-resistant bacteria can be involved, making the treatment challenging and bear an anthropo-zoonotic potential. The aim of this review is to systematically evaluate based on recent scientific literature, the potential of four medicinal plants to enrich the therapeutic options in pyoderma, canine atopic dermatitis, otitis externa, wounds and dermatophytosis in dogs.

Results

Based on four books and a survey among veterinarians specialized in phytotherapy, four medicinal plants were chosen as the subject of this systematic review: Calendula officinalis L. (Marigold), Hypericum perforatum L. agg. (St. John’s Wort), Matricaria chamomilla L. (syn. Matricaria recutita L., Chamomile) and Salvia officinalis L. (Sage). According to the PRISMA statement through literature research on two online databases a total of 8295 publications was screened and narrowed down to a final 138 publications for which full-text documents were analyzed for its content resulting in a total of 145 references (21 clinical, 24 in vivo and 100 in vitro references).

Conclusions

All four plants were proven to have antibacterial and antifungal effects of a rather broad spectrum including antibiotic-resistant bacteria. This makes them an interesting new option for the treatment of pyoderma, otitis externa, infected wounds and dermatophytosis. Marigold, St. John’s Wort and Chamomile showed wound-healing properties and are thus promising candidates in line to fill the therapeutic gap in canine wound-healing agents. St. John’s Wort and Chamomile also showed anti-inflammatory and other beneficial effects on healthy skin. Due to the wide range of beneficial effects of these medicinal plants, they should be taken into account for the treatment of dermatologic diseases in dogs at least in future clinical research.

Electronic supplementary material

The online version of this article (10.1186/s12917-019-1854-4) contains supplementary material, which is available to authorized users.

[Arzneipflanzen im Berner Pferdestall: Erfahrungswissen von Pferdehaltern]

Hintergrund: Während über den traditionellen Einsatz von Arzneipflanzen durch Landwirtinnen und Landwirte beim Nutztier sowohl in Südeuropa als auch in der Schweiz zunehmend wissenschaftliche Veröffentlichungen vorliegen, fehlen gezielte Studien mit Pferdebesitzern weitestgehend. Mit der vorliegenden Studie sollte dieses Wissen exemplarisch für den Schweizer Kanton Bern erfasst werden. Probanden und Methoden: Methodisch an vorhergehende Studien in der Schweiz angelehnt, wurden von 2011-2012 7 Pferdehalter im Alter von 24-65 Jahren anhand eines semistrukturierten Fragebogens zum Einsatz von Arzneipflanzen bei ihren Pferden interviewt. Neben Informationen zu Pflanzenarten und Pflanzenteilen wurden die Zubereitung und Anwendung (inklusive Dosierung) der Rezepturen detailliert dokumentiert. Ergebnisse: Insgesamt wurden 21 Rezepturen von den Berner Pferdehaltern genannt, von denen 4 Mischungen aus 2-5 verschiedenen Pflanzenarten waren. In den Rezepturen wurden 27 Pflanzenarten aus 22 Pflanzenfamilien verwendet. Für mehr als 50% der Rezepte wurden die Arzneipflanzen in der Apotheke gekauft, jedoch lediglich für 1 (4%) beim Tierarzt; für ein weiteres Drittel der Rezepte wurden Pflanzen gesammelt. Für die 21 Rezepturen wurden 30 Anwendungen beschrieben, vor allem zur Behandlung der Haut, des Bewegungsapparats und der Atemwege. Am häufigsten wurden Anwendungen von Ingwer (Zingiber officinale) und Johanniskraut (Hypericum perforatum) genannt. Beide Pflanzen werden überwiegend zur innerlichen (Ingwer) bzw. äußerlichen Behandlung (Johanniskrautblütenöl) von Erkrankungen des Bewegungsapparats eingesetzt. Schlussfolgerungen: Gemessen an der Zahl der interviewten Pferdehalter kommt im Kanton Bern traditionell ein breites Spektrum von Arzneipflanzen beim Pferd zum Einsatz. Auch wenn Tierärzte aktuell kaum als Bezugsquelle für Arzneipflanzen dienen, dürfte das Potenzial für die tierärztliche Phytotherapie in der Pferdemedizin groß sein.

Monoamine Oxidase-A Inhibition and Associated Antioxidant Activity in Plant Extracts with Potential Antidepressant Actions

Monoamine oxidase (MAO) catalyzes the oxidative deamination of amines and neurotransmitters and is involved in mood disorders, depression, oxidative stress, and adverse pharmacological reactions. This work studies the inhibition of human MAO-A by Hypericum perforatum, Peganum harmala, and Lepidium meyenii, which are reported to improve and affect mood and mental conditions. Subsequently, the antioxidant activity associated with the inhibition of MAO is determined in plant extracts for the first time. H. perforatum inhibited human MAO-A, and extracts from flowers gave the highest inhibition (IC₅₀ of 63.6 μg/mL). Plant extracts were analyzed by HPLC-DAD-MS and contained pseudohypericin, hypericin, hyperforin, adhyperforin, hyperfirin, and flavonoids. Hyperforin did not inhibit human MAO-A and hypericin was a poor inhibitor of this isoenzyme. Quercetin and flavonoids significantly contributed to MAO-A inhibition. P. harmala seed extracts highly inhibited MAO-A (IC₅₀ of 49.9 μg/L), being a thousand times more potent than H. perforatum extracts owing to its content of β-carboline alkaloids (harmaline and harmine). L. meyenii root (maca) extracts did not inhibit MAO-A. These plants may exert protective actions related to antioxidant effects. Results in this work show that P. harmala and H. perforatum extracts exhibit antioxidant activity associated with the inhibition of MAO (i.e., lower production of H₂O₂).

Hypericum perforatum (St John's wort) beyond depression: A therapeutic perspective for pain conditions

ETHNOPHARMACOLOGICAL RELEVANCE

Hypericum perforatum L. (Hypericaceae), popularly called St. John's wort (SJW), has a rich historical background being one of the oldest used and most extensively investigated medicinal herbs. Many bioactivities and applications of SJW are listed in popular and in scientific literature, including antibacterial, antiviral, anti-inflammatory. In the last three decades many studies focused on the antidepressant activity of SJW extracts. However, several studies in recent years also described the antinociceptive and analgesic properties of SJW that validate the traditional uses of the plant in pain conditions.

AIM OF THE REVIEW

This review provides up-to-date information on the traditional uses, pre-clinical and clinical evidence on the pain relieving activity of SJW and its active ingredients, and focuses on the possible exploitation of this plant for the management of pain.

MATERIALS AND METHODS

Historical ethnobotanical publications from 1597 were reviewed for finding local and traditional uses. The relevant data on the preclinical and clinical effects of SJW were searched using various databases such as PubMed, Science Direct, Scopus, and Google Scholar. Plant taxonomy was validated by the database Plantlist.org.

RESULTS

Preclinical animal studies demonstrated the ability of low doses of SJW dry extracts (0.3% hypericins; 3-5% hyperforins) to induce antinociception, to relieve from acute and chronic hyperalgesic states and to augment opioid analgesia. Clinical studies (homeopathic remedies, dry extracts) highlighted dental pain conditions as a promising SJW application. In vivo and in vitro studies showed that the main components responsible for the pain relieving activity are hyperforin and hypericin. SJW analgesia appears at low doses (5-100mg/kg), minimizing the risk of herbal-drug interactions produced by hyperforin, a potent inducer of CYP enzymes.

CONCLUSION

Preclinical studies indicate a potential use of SJW in medical pain management. However, clinical research in this field is still scarce and the few studies available on chronic pain produced negative results. Prospective randomized controlled clinical trials performed at low doses are needed to validate its potential efficacy in humans.

Dietary flavonoids and modulation of natural killer cells: implications in malignant and viral diseases

Flavonoids are a large group of secondary plant metabolites present in the diet with numerous potentially health-beneficial biological activities. In addition to antioxidant, anti-inflammatory, cholesterol-lowering, and many other biological functions reported in the literature, flavonoids appear to inhibit cancer cell proliferation and stimulate immune function. Although the immunomodulatory potential of flavonoids has been intensively investigated, only little is known about their impact on natural killer (NK) cells. Enhancing NK cell activity, however, would have strong implications for a possible clinical use of flavonoids, especially in the treatment and prevention of diseases like cancer and viral infections. Therefore, the purpose of this review is to summarize the currently available information on NK cell modulation by flavonoids. Many of the structurally diverse flavonoids stimulate NK cell activity and have thus great potential as diet-derived immune-modulatory chemopreventive agents and may even serve as therapeutic compounds or lead structures for the development of novel drugs for the treatment of both malignant and viral diseases.

Medicinal plants used for musculoskeletal disorders in Navarra and their pharmacological validation

ETHNOPHARMACOLOGICAL RELEVANCE

This paper provides important ethnopharmacological information on plants used in musculoskeletal disorders in Navarra.

MATERIAL AND METHODS

Information was collected using semi-structured ethnobotanical interviews. In order to confirm the pharmacological validation of the uses, monographs from Official International Agencies (ESCOP, Commission E, WHO and EMA) were reviewed. A literature review was conducted focusing on the plants that were widely used but had no published monograph.

RESULTS

A total of 199 pharmaceutical uses were reported, for 38 plants and 24 families, mainly represented by Asteraceae and Lamiaceae (11%, each), Rosaceae (8%) and Boraginaceae, Cucurbitaceae, Equisetaceae, Malvaceae, Oleaceae and Urticaceae (5%, each). The most frequently used parts were the aerial parts, roots, followed by inflorescences and leaves. Nine out of 38 plants (24%) and 123 uses (62%), had already been pharmacologically validated.

CONCLUSIONS

The authors propose to validate four species for their use in musculoskeletal disorders: Verbena officinalis, Symphytum tuberosum, Hypericum perforatum and Equisetum ssp.

Effects of the total flavonoid extract of Xiaobuxin-Tang on depression-like behavior induced by lipopolysaccharide and proinflammatory cytokine levels in mice

ETHNOPHARMACOLOGICAL RELEVANCE

Xiaobuxin-Tang (XBXT), a traditional Chinese herbal decoction, has been used for the treatment of depressive disorders from ancient clinic. The aim of the study was to explore the involvement of inflammation or inflammatory markers in the antidepressant-like effects of XBXT-2.

MATERIALS AND METHODS

Depression-like behavior was induced by lipopolysaccharide (LPS, 0.2mg/kg, i.p) in tail suspension test (TST) and forced swimming test (FST) in mice. The effects of the total flavonoids (XBXT-2) extracted from XBXT (25, 50, and 100mg/kg, p.o.) and duloxetine (DLX, 10mg/kg, p.o.) on the immobility time in TST and FST were determined 24h after LPS pretreatment. The locomotor activity was also determined to eliminate the false-positive activity. Additionally, in order to further evaluate the effect of XBXT-2 on inflammation, the levels of brain proinflammatory cytokines including IL-1β and TNF-α were assessed by ELISA.

RESULTS

The pretreatment with LPS significantly increased the immobility time in TST and FST in mice, as well as the brain levels of IL-1β and TNF-α. XBXT-2 (25, 50, and 100mg/kg, p.o.) administration decreased the duration of immobility in TST and FST, and normalized the cytokines levels. The positive control DLX (10mg/kg, p.o.) exerted similar effects. Meanwhile, neither LPS pretreatment nor drugs treatment had any effect on mouse locomotor activity.

CONCLUSIONS

These results suggest that inflammation and inflammatory cytokines may be involved in the antidepressant-like effects of XBXT-2.